To solve this question, the user needs to know who Andre Agassi is and how many Grand Slam titles he has won.

Now, let's go through each option and explain why it is right or wrong:

A. 9: This option is incorrect because Andre Agassi has won 8 Grand Slam titles in his career, not 9.

B. 7: This option is incorrect because Andre Agassi has won 8 Grand Slam titles in his career, not 7.

C. 6: This option is incorrect because Andre Agassi has won 8 Grand Slam titles in his career, not 6.

D. 8: This option is correct. Andre Agassi has won 8 Grand Slam titles in his career, which includes:

• 4 Australian Open titles (1995, 2000, 2001, 2003)
• 2 US Open titles (1994, 1999)
• 1 Wimbledon title (1992)
• 1 French Open title (1999)

Therefore, the correct answer is:

The Answer is: D